package com.virgil.core.utils;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

@Component
public final class SpringContextUtil implements ApplicationContextAware {

    
  //ApplicationContext对象是Spring开源框架的上下文对象实例，在项目运行时自动装载Handler内的所有信息到内存。
    private static ApplicationContext applicationContext;
    
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        if (SpringContextUtil.applicationContext == null) {
        	SpringContextUtil.applicationContext = applicationContext;
        }
    }
    
    //获取applicationContext
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }
    
    //通过name获取 Bean.
    public static Object getBean(String name) {
        return getApplicationContext().getBean(name);
    }
    
    //通过class获取Bean.
    public static <T> T getBean(Class<T> clazz) {
        return getApplicationContext().getBean(clazz);
    }
    
    //通过name,以及Clazz返回指定的Bean
    public static <T> T getBean(String name, Class<T> clazz) {
        return getApplicationContext().getBean(name, clazz);
    }
}
